Authorized online music took another big step forward Thursday, as the world's two largest record companies said they will roll out their long-planned music-subscription service on Web portal Yahoo! this summer.

Sony Music Entertainment and Universal Music Group, whose formidable artist rosters include Limp Bizkit, Jennifer Lopez, DMX, Pearl Jam and Destiny's Child, plan to offer both downloadable and streaming, on-demand music through the service, called Duet.

The announcement, which follows Monday's revelation that the other three major record companies will offer a similar service through America Online and elsewhere, includes a Napster-like twist. After paying a set monthly fee for music access, users will be able to swap their personalized music playlists with each other, allowing them to share music without moving files from computer to computer.

In a press conference Thursday afternoon (April 5), Sony and Universal executives said they hoped to license Duet to other sites and services. They did not rule out the possibility that Napster could be one of their licensees, assuming the file-sharing service debuts its promised copyright-friendly subscription service.

Executives did not release details on pricing for the service, or on how many songs and albums will be available.

On Monday, Warner Music Group, BMG Entertainment and EMI Recorded Music announced the formation of MusicNet, a jointly owned company that will license their music to subscription services (see "Labels Announce Joint Venture To License Music").

The MusicNet companies expressed hope that Sony and Universal would join their venture, while the Duet partners, in turn, said they hoped BMG, Warner and EMI would join Duet.

But at this point, music fans will need to subscribe to at least two services if they want to emulate the broad selection of music Napster offered until a recent court injunction forced it to begin screening out copyrighted music.

The MTVi Group, meanwhile, said Wednesday that it will soon begin offering downloadable music from all five major record companies on MTV.com and VH1.com, courtesy of partner RioPort. MTVi's plan  which is intended to allow fans to download tracks they hear on the company's online radio offerings  will offer music on a pay-per-download basis, rather than by subscription.

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